Thomas noethey



(No Model.)

T. NORTHEY.

AUTOMATIC LOW WATER INDICATOR.

teuted Sept. 11, 1888.

UNITED STATES PATENT OFFICE.

,THoMAs NonTHnY, or TORONTO, ONTARIO, CANADA.

AUTOMATIC LOW-WATER INDICATOR.

SFECFCATON forming part of Letters Patent No. 389.240, dated September 1l, 1888.

(No model.)

To @ZZ whom t may concern.-

Beitknown that LTHoMAs NORTHEY, asubject of the Queen of Great Britain, and a resident of Toronto, in the Province of Ontario and Dominion of Canada, have invented certain new and useful Improvements in Automatic Low-W'ater Indicators; and l do hereby declare that the following is a full, clear, and exact description of the invention, which will enable others skilled in the art to which it appertains to make and use the same, reference beinghad totheaccompanyingdrawings,which form a part of this specification, and in which- Figure 1 is a central longitudinal vertical sectional View of my new and improved lowwater indicator, showing the same secured in operative position ina boiler. Fig. 2 is a seetional view of theindieator, taken on the plane indicated by line x .fr on Fig. l, showing the valve-chamber in full lines. Fig. 3 is a central vertical sectional view of the valve-chamber and whistle, ofthe size of aworking indicator. Fig. 4 is a transverse sectional View of the entire device, taken on line .c x of Fig. 1, fullsize; and Fig. 5 is avertical sectional view taken on the plane indicated by line 1/ y of Fig. 4.

rlhe same letters of reference indicate corresponding parts in all the figures.

My invention eonsistsin anew and improved automatic low-water detector or indicator for stearnAboilers, which will be hereinafter fully described and claimed.

Referring to the several parts by letter, A indicates an open cast-iron column, open on its sides, which is usually about thirty-four inches long, and which is formed at its lower end with an exterior screw-thread, B, to enable it to be screwed into the boiler C of any construction. .Vithin this open column is secured the curved hollow rod ortube D, which operates automatically to open the valve and sound the whistle when the water has fallen below a certain point. This tube is threaded externally at its lower end, and is screwed at its lower end in the base of the column, as shown, while it is held rmly at its top by the cap E, which is screwed down on the upper end of column A and adjusted to the upper closed pointed end of the bent tube, when it is secured permanently in position on the top of the column by a small screw, F, which is screwed through the lower part of the cap and to upper end of the column A. The lower side of the top of the cap is formed with a small central depression, G, in which ts the pointed upper solid end, H, of the bent tube.

The tube D is bent or curved to one side, as shown clearly in Fig. l of the drawings, and it'will be seen that as this tube is rmly fastened at both ends it cannot expand or contract by heat or cold in the direction of its length, but is forced to move back and forth to and from the inner end of the spindle of the valve, hereinafter described, the bend or curve of the tube being increased when the tube is expanded and the tube straightening to its normal position when cold.

The lower end ofthe column is threaded interiorly at l for the attachment by its upper threaded end ofthe lower pipe, J, the open lower end of which extends down to about an inch (or to any given point) below the proper car- Tying-level of the water in the boiler, as shown in Fig. l of the drawings.

In the base of the column A is screwed the lower threaded end ol' the pipe K, which has at its upper end the valve and whistle. An opening, L, leads from the lower Open end of this pipe K into the interior of the boiler. Upon the upper end of this tube K is secured the valve-chamber M, which is formed with the narrow valveseat N, as shown, upon which the valve O fits. rlhe face P of this valve is made conical, working on the very narrow seat N to prevent grit, the., from lodging on the valve-seat. The front or inner side ofthe valve is concave to permit of the inner end of the conical guide Q, which is formed on that side of the valve-chamber, fit-ting or projecting inward within the said concaved side of the valve, as shown. The valve-spindle R ex tends through this guide Q into the side of the open column A, and it will be seen that by forming the guide ofthe conical shape shown, with its inner end fitting into the concaved front side of the valve, the valve spindle will be covered completely, so that, being out of the direction of the steam as it passes from the boiler to the whistle, any grit, dre., will be prevented from being blown into it, which would otherwise obstruct the free action of the ICO valve. The outer bore of the guide Q is enlarged, as shown, so as to allow the valve to work as freely as possible.

The opposite sides of the valve-chamber are formed with the guide-lugs S S, and the column A is formed at that point with the stops T T, which project out from that side of the column A on each side of the valve-chamber, and are formed with the inward1ybent outer ends, U U, and are recessed on their inner sides with the Wide recesses V V, the widthof which is about three times as great as the diameter of the lugs S S. The lugs S S iit and play in these horizontal recesses in the inner sides of the stops, and these stops serve to protect the Valve-'chamber and prevent it from being pressed away from the bent tube D when in operation; also, by forming the recesses V of the width shown, should the valve become choked by grit or any foreign substance by its partial opening while in action the valve can be manipulated by hand by pressing the valvechamber on the upper end of the small tube K back in until the projecting end of the valvespindle comes in contact with the bent tube D, when the valve will be opened to its full extent, thereby clearing it as the steam rushes through. By forming the recesses in the inner side of the stops wider than the diameter of the lugs S on each side of the valve-chamber it will be seen that the fitting of the parts will be facilitated, and the expansion and contraction of the pipe K are also allowed for.

At the back of the valve-chamber is a nut or plug, W, which is removed to place the valve in position or to give ready access to the same at any time desired. A small spiral spring, A', is placed at the back ofthe valve, encircling that end of the valve-spindle, the function of this spring being to cause the valve to close when there is no pressure'in the boiler. The operation of my new and improved low-water detector and alarm is as follows: In its normal position, when the water in the boiler is above the level of the lower end of the pipe J, the water is forced up in the curved tube D, which is curved toward the v alvechamber, and the water will cool this tube and keep it in its normal position. (Shown in the drawings.) The pipe K will always be full of steam, and this steam will press against the back of the valve and hold the valve firmly to its narrow seat independently of the action of the spring A. A whistle, B', is secured, as shown, upon the upper end of the valvechamber, so as to be blown by the steam when the valve is open. As soon as the water in the boiler falls below the orifice in the lower end of pipe J, the water in pipe J and tube D will fall into the boiler, and the steam will enter at the lower end of pipe J and pass up and till the curved tube D. The steambeing a good radiator of heat, readily imparts its heat to the curved tube, causing the same to expand over to the side of the column A, when the center of the tube D (which is usually about thirty inches long) will press against seaz the outer end of the valve'spindle and force the valve off of its narrow seat, when the steam from the boiler will rush through the valve-chamber to the whistle, causing it to sound. It will be seen that as long as the level of the water is below the lower end of pipe J that. the steam will iill the tube D,"and as long as the tube D is thus heated and expanded it will hold the valve open and cause the whistle to continuously sound. As soon as the water rises in the boiler and covers the open lower end of pipe J it will be driven up into the curved tube or pipe D, almost immediately cooling the pipe by radiation to a low temperature, causing it to contract and draw away from the valvespindle, allowing the valve to close, when the whistle stops.

It will be seen that the single-curved tube D will operate automatically by expansion and contraction, and, through the valve and whistle, which it works, indicate when the water in the boiler falls below a certain level and when it rises above this level.

Having thus described my invention,what I claim,and desire to secure by Letters Patent of the United States, is-

1. The combination, in alow-water indicator for boilers, of a pipe leading from the upper part of the boiler and having at its upper end a valve-seat controlled by a valve the spindle of which projects out at one side, and a whistle controlled by thesaid valve, and a metal tube slightly curved toward the side valve firmly held at both ends, having a closed upper end and communicating at its lower end with the interior of the boiler below the normal waterlevel of the same.

2. The combination ofthe open column having the cap at its upper end, the threads formed at its base, and the small opening extending through one side of its base, the pipe extending from the lower end of this column, the curved tube having the closed upper end and secured within the column, as described, the tube having the valve-chamber formed with the seat and the whistle at its upper end, and the conical valve having the projecting spindle, substantially as set forth.

3. The combination of the open column having the cap at its upper end, the parallel recessed lugs, the threads formed at its base, and the small opening extending through one side of its base, the pipe extending down from the lower end of the column, the curved tube having the closed upper end and firmly secured at both ends within the column, the side tube, tlie valve-chamber formed with the side lugs and the valve-seat, the whistle, and the conical valve having the projecting spindle, substantially as set forth.

4. The combination of the open column having the end cap, the parallel recessed lugs, the threads formed at its base, and the small opening extending through one side of its base, the pipe extending down from the lower end of the column, the curved tube having the closed upper end and firmly secured at both ICO ends within the column, the side tube, the own I have hereunto afxed my signature in valve-chamber formed with the side lugs, the presence of two witnesses.

narrowseat andthe conical guide the Whistle, T 1 r the conical 7concave Valve having7 the projeot- THOMAS NORTHB' 5 ing spindle, and the spring, substantially as Vitnesses:

and for the purpose set forth. Jos. H. FOSTER,

In testimony that I claim the foregoing as my H. E. MORPHY. 

